Emergency opening latch



Nov. 18, 1969 c, B'ANAS Re. 26,711

EMERGENCY OPENING LATCH Original Filed March 11, 1966 INVENTOR UnitedStates Patent 26,711 EMERGENCY OPENING LATCH Henry C. Banas, Costa Mesa,Califi, assignor, by mesne assignments, to McDonnell DouglasCorporation, Santa Monica, Calif., a corporation of Maryland OriginalNo. 3,338,609, dated Aug. 29, 1967, Ser. No. 533,468, Mar. 11, 1966.Application for reissue Oct. 2, 1967, Ser. No. 682,689

Int. Cl. E051: 9/04, 15/02 US. Cl. 292-21 Claims Matter enclosed inheavy brackets appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A hinge pin type of latch which securelyfastens a flange located on an aircraft door to a flange located on anemergency slide container. The hinge pin is composed of three separatesections, a centrally located section and two outer sections. The outersections are pivotally mounted to the central section and establish anover-center looking action which maintains the latching of the flanges.A pulling force applied to the central section causes the outer sectionsof the pin to pivot toward the central sections and be dislodged fromthe flanges, thereby opening the container This invention relates to alatch and more particularly to a latch which is to be employed in anemergency door of an aircraft.

In the commercial transportation field it is necessary to include in thevehicles a means to permit emergency evacuation of the passengers. Inland vehicles such a problem can be easily solved by means of a door ordoors and stairway arrangement. However, emergency evacuation means inaircraft have always been a problem. The problem is further complicatedin aircraft as aircraft are more subject to fire and explosion requiringquick passenger evacuation. Also, the aircraft fuselage is spacedseveral feet above the ground which requires some means to allow thepassengers to descend without injury.

Therefore, it is required that upon opening a door of an aircraft in anemergency, a passenger evacuation slide is deployed Within a fewseconds. Such a slide can be conveniently mounted on the inside of anaircraft door within a container, the slide being inflatable. The container must be opened as quick as possible without any delay. It is alsodesirable that upon the single opening movement of the aircraft door,the container is opened and the slide is employed automatically.

A latch which is required to open and close such a container must be ofsufficient strength to retain high loads, be positive in retention, bereusable, require W opening force to be applied from several ditferentdirections, yet be small enough to present no obstacle to the passengersemerging from the aircraft by the evacuation slide. The latch of thisinvention accomplishes the above objectives with great assurance.

Briefly the latch of this invention relates to a hinge pin type of thelatch which securely fastens a flange located on the aircraft door to aflange located on the side container. The hinge pin is composed of threeseparate sections, a centrally located section and two outer sections.The outer sections are pivotally mounted to the central section andestablish an over-center locking action which maintains the latching ofthe flanges. A pulling force applied to the central section causes theouter sections of the pin to pivot toward the central sections and bedislodged from the flanges, thereby opening the container.

Re. 26,711 Reissuted Nov. 18, 1969 Other objects and features of theinvention will become apparent as the description proceeds, particularlywhen taken in conjunction with the accompanying drawings illustratingthe invention wherein:

FIGURE 1 is a perspective view of the latch of this invention in theoperable position;

FIG. 2 is an exploded view of the latch of this invention showing thelatch when disassembled;

FIG. 3 is a view showing the latch as installed in the evacuation slidecontainer; and

FIG. 4 is a view similar to FIG. 3 but showing the container in theready emergency condition.

The description of the latch per se without regard for its particularinstallation will be had noting particularly FIGURES l and 2. In FIGURES1 and 2 flanges 10 and 12 are shown, flange 10 to be fixed to theaircraft and flange 12 to be mounted on the evacuation slide container.Each flange 10 and 12 has protruding arms 14 and 16, respectively, arms14 being adapted to contact arms 16. Pin 18 is to be mounted betweenarms 14 and 16 when in the operative position.

Pin 18 is composed of a central section 20 and pivotal outer sections 22and 24. Central section 20 is substantially T-shaped with outer sections22 and 24 pivotally secured to the outer edges of the T member by meansof pivot pins 26 and 28, respectively. Outer sections 22 and 24 aresubstantially cylindrical in shape with the pivot pins 26 and 28 mountedoff center toward the top portion of the central section 20. Outersections 22 and 24 contain slots 30 and 32, respectively, the edges ofthe T- shaped central section 20 being pivotal within said slots. Thedepth of each slot 30 and 32 is sufficient to permit the outer sections22 and 24 to assume a straight line configuration. On the single leg ofthe T-shaped central section 20 a rotating member 34 is pivotallysecured by means of pivot pin 36. Rotating member 34 and outer sections22 and 24 are pivotal within a single plane, the plane of the T-shapedcentral section. A lanyard 38 is aflixed to the rotating member 34 whichis to be the means to disengage the latch from the flanges 10 and 12. Ascan be seen from the drawing this particular arrangement has a uniqueadvantage. The outer sections 22 and 24 when established between theflanges 10 and 12 by means of protuberances 42 and 44 on the outerportion of each outer section 22 and 24, respectively, in apertures inthe arms 14 and 16. The resultant installation operates similar to ahinge in that they can be rotated about a center line through the arms14 and 16. Rotating member 34 is rotatable on central section 20 about acenter line through pivot pin 36, the rotation being perpendicular tothe rotation of the outer sections 22 and 24. By such rotation adisconnection force applied through lanyard 38 within the confines ofthe cone shown in dotted lines in FIG. 1 will disconnect the latch. Ithas been found that a cone of about is more than adequate.

Because of the over-center locking action of the outer sections 22 and24, only a relatively small release force is required. However, whilelatched the locking action is sure and positive, it being impossible toaccidentally remove the latch. Upon disengagement, the latch can beeasily reinstalled thereby negating the use of another latch pin. Thelatch is reinstalled by manually inserting the outer sections 22 and 24into the arms 14 of flange 12 establishing the over-center lockingaction. The container is then closed causing the arms 14 to contact thearms 16 of flange 10. The arms 16 are flared as at 40 to facilitate easeof connection.

In FIGURES 3 and 4 is shown a slide container mounted on an aircraftdoor 48 with the latch of this invention afiixed thereto. In FIG. 3 thecontainer 50 is closed with the latch of this invention preventingopening of the container 50. A bar 52 is provided which is connected toan extended portion 54 of the evacuation slide contained within thecontainer 50. When the door 48 is not to be used for an emergencypurpose, the bar 52 is mounted on the front of the container 50 by clips56 as shown in FIG. 3. In this manner no relative movement isestablished between the container 50 and the bar 52 which would causethe opening of the container.

In FIG. 4 the bar 52 is mounted preparatory to an emergency. Bar 52 isfixed to the interior floor of the aircraft by means of fastening means58. The lanyard 38 is of a length that when bar 52 is in this positionthe lanyard is taut. Also, the extended portion of the slide 54 is tautin this position.

The operation of the slide is as follows: As the aircraft door 48 isopened a pulling force is applied through lanyard 38 operating on thecentral section 20 of the pin 18. Thereupon, the outer sections 22 and24 are withdrawn from the arms 14 and 16 causing the container to beopened. As the aircraft door 48 is opened further the slide is withdrawnfrom the container as extended portion 54 is attached to the bar 52. Theevacuation slide falls free by the pull of gravity and is automaticallyinflated. The total time lapse from the opening of the aircraft door tothe inflation of the evacuation slide (ready for use) in less than eightseconds. Such speed is absolutely necessary in some emergencysituations.

Having thus described the invention in relation to an evacuation slidein an aircraft, it is to be understood that the invention should in noway be limited thereto, but is applicable in other environments whenevera quick release latch is desired.

I claim:

1. [An emergency opening latch comprisingfl A combination, for openingan evacuation slide container in an aircraft, comprising:

a first flange member fixed/y secured to the aircraft; a second flangemember fixedly secured to the evacuation slide container; a removableconnecting pin having:

a central coupling section [having a depending leg portion and uppertransverse arm portions]; [an] outer sections pivotally connected to[each of said upper transverse arm portions] said cen tral couplingsection, said outer sections being pivotal from a substantial in-linearrangement to a position approximately at a right angle therefrom, saidouter sections establishing an over-center locking action when in saidin-line arrangement, said outer sections being rotatably connected[connectable] to [a fixed member] said first and second flange membersestablishing a hinge type of [action] connection;

[an arm member pivotally secured to said central coupling section atsaid depending leg portion;] and a releasing means being [secured]connected to said [arm member] central coupling section whereby upon anadequate pulling force exerted upon said releasing means, said outersections are pivoted with respect to said central coupling section anddisengaged from said flange members [fixed member].

2. [An emergency opening latch as defined in] the combination of claim 1wherein:

said releasing means is a lanyard.

3. The combination of claim 1 wherein:

said releasing means being pivotally connected with respect to saidcentral coupling section.

4. An emergency opening latch comprising:

a central coupling section having a depending leg portion and uppertransverse arm portions;

an outer section pivotally connected to each of said upper transversearm portions, said outer section being pivotal from a substantialin-line arrangement to a position approximately at a right angletherefrom, said outer section establishing an over-center locking actionwhen in said in-line arrangement, said outer section being rotatablyconnectable to a fixed member establishing a hinge type of action;

an arm member pivotally secured to said central coupling section at saiddepending leg portion; and

a releasing means being secured to said arm member whereby upon anadequate pulling force exerted upon said releasing means, said outersection is pivoted with respect to said central section and disengagedfrom said fixed member.

5. The emergency opening latch of claim 1 wherein:

said releasing means is a lanyard.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 566,856 9/1896 Frost 2926 2,461,693 2/1949 McAloon24-265 2,931,205 4/1960 Schmitz 29292 X 2,292,386 8/1942 Manson 244l22FOREIGN PATENTS 1,008,030 5/ 1957 Germany.

MARVIN A. CHAMPION, Primary Examiner J. R. MOSES, Assistant Examiner

